1. Field of the Invention
This invention relates to silicone compositions which exhibit an excellent adhesiveness and to a method of adhering silicone rubber to a substrate.
2. Description of the Prior Art
Conventionally, various primer compositions have been proposed for adhesion between silicone rubber and metals, between silicone rubber and different types of materials other than silicone rubber and between silicone rubbers. However, a satisfactory composition has not been found and investigations are continuing. Because silicone rubbers have characteristics such as mold releasability, heat resistance, electrical properties, chemical resistance, and solvent resistance, silicone rubbers have been used as embossing rolls for polyvinyl chloride, calender touch roll, extrusion laminating rolls and antistatic electricity rolls. In any of these cases, from a consideration of economic efficiency, a relatively inexpensive material is used in the layers below the roll surface layer. Thus, the adhesion between silicone rubber and the inexpensive material is always a matter of concern. Even for adhesion between silicone rubbers, adhesion becomes extremely difficult when different crosslinking systems are used. For example, adhesion is extremely difficult between a silicone rubber using an organic peroxide as the crosslinking agent and a silicone rubber obtained by an addition reaction or between a fluorosilicone rubber and a dimethylsilicone rubber. These problems cannot be satisfactorily solved using conventional primer compositions. Therefore, the poor adhesion between silicone rubber and organic materials using conventional primer compositions frequently cause trouble.